Set linux test running system to ubuntu-22.04 and bump nacos docker version of dubbo-samples-nacos-legacy to V2.5.1-slim (#76)

* Bump dubbo-samples-nacos-legacy nacos server to V2.5.1-slim

* Running test on ubuntu-22.04 to support legacy cgroup v1 for zk and nacos server
diff --git a/.github/workflows/dubbo-3_2.yml b/.github/workflows/dubbo-3_2.yml
index 1e8403c..75909c7 100644
--- a/.github/workflows/dubbo-3_2.yml
+++ b/.github/workflows/dubbo-3_2.yml
@@ -31,7 +31,7 @@
 jobs:
   build-samples:
     needs: [build-dubbo]
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     strategy:
       fail-fast: false
     steps:
@@ -56,7 +56,7 @@
           ./mvnw --batch-mode --no-snapshot-updates --no-transfer-progress --settings ${{github.workspace}}/.mvn/settings.xml clean
 
   build-dubbo:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     strategy:
       fail-fast: false
     # Map a step output to a job output
@@ -106,7 +106,7 @@
           ./mvnw --batch-mode --no-snapshot-updates --no-transfer-progress  clean install -Dmaven.test.skip=true -Dmaven.test.skip.exec=true
 
   prepare_test:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     env:
       #'JOB_COUNT' MUST match 'job_id' list of 'testjob'
       JOB_COUNT: 5
@@ -124,7 +124,7 @@
   testjob:
     needs: [prepare_test, build-dubbo]
     name: 'Integration Test (Java${{matrix.java}}, Job${{matrix.job_id}})'
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     env:
       JAVA_VER: ${{matrix.java}}
       TEST_CASE_FILE: jobs/testjob_${{matrix.job_id}}.txt
@@ -180,7 +180,7 @@
     needs: [testjob]
     name: 'Test Result (Java${{matrix.java}})'
     if: always()
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     strategy:
       fail-fast: false
       matrix:
diff --git a/.github/workflows/dubbo-3_3.yml b/.github/workflows/dubbo-3_3.yml
index 64b811b..477c28f 100644
--- a/.github/workflows/dubbo-3_3.yml
+++ b/.github/workflows/dubbo-3_3.yml
@@ -31,7 +31,7 @@
 jobs:
   build-samples:
     needs: [build-dubbo]
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     strategy:
       fail-fast: false
     steps:
@@ -56,7 +56,7 @@
           ./mvnw --batch-mode --no-snapshot-updates --no-transfer-progress --settings ${{github.workspace}}/.mvn/settings.xml clean
 
   build-dubbo:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     strategy:
       fail-fast: false
     # Map a step output to a job output
@@ -106,7 +106,7 @@
           ./mvnw --batch-mode --no-snapshot-updates --no-transfer-progress  clean install -Dmaven.test.skip=true -Dmaven.test.skip.exec=true
 
   prepare_test:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     env:
       #'JOB_COUNT' MUST match 'job_id' list of 'testjob'
       JOB_COUNT: 5
@@ -124,7 +124,7 @@
   testjob:
     needs: [prepare_test, build-dubbo]
     name: 'Integration Test (Java${{matrix.java}}, Job${{matrix.job_id}})'
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     env:
       JAVA_VER: ${{matrix.java}}
       TEST_CASE_FILE: jobs/testjob_${{matrix.job_id}}.txt
@@ -180,7 +180,7 @@
     needs: [testjob]
     name: 'Test Result (Java${{matrix.java}})'
     if: always()
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     strategy:
       fail-fast: false
       matrix:
diff --git a/.github/workflows/license.yml b/.github/workflows/license.yml
index 16e197e..59482df 100644
--- a/.github/workflows/license.yml
+++ b/.github/workflows/license.yml
@@ -7,10 +7,10 @@
 
 jobs:
   license:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     steps:
       - uses: actions/checkout@v3
       - name: Check License
         uses: apache/skywalking-eyes@main
         env:
-          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
\ No newline at end of file
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
diff --git a/.github/workflows/nightly-dubbo-3.yml b/.github/workflows/nightly-dubbo-3.yml
index 7560c42..f7d3f52 100644
--- a/.github/workflows/nightly-dubbo-3.yml
+++ b/.github/workflows/nightly-dubbo-3.yml
@@ -30,7 +30,7 @@
 
 jobs:
   build-samples:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     strategy:
       fail-fast: false
       matrix:
@@ -54,7 +54,7 @@
           ./mvnw $BUILD_OPTS
 
   build-dubbo:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     strategy:
       fail-fast: false
     # Map a step output to a job output
@@ -104,7 +104,7 @@
           ./mvnw --batch-mode --no-snapshot-updates --no-transfer-progress  clean install -Dmaven.test.skip=true -Dmaven.test.skip.exec=true
 
   prepare_test:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     env:
       #'JOB_COUNT' MUST match 'job_id' list of 'testjob'
       JOB_COUNT: 5
@@ -122,7 +122,7 @@
   testjob:
     needs: [prepare_test, build-dubbo]
     name: 'Integration Test (Java${{matrix.java}}, Job${{matrix.job_id}})'
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     env:
       JAVA_VER: ${{matrix.java}}
       TEST_CASE_FILE: jobs/testjob_${{matrix.job_id}}.txt
@@ -177,7 +177,7 @@
     needs: [testjob]
     name: 'Test Result (Java${{matrix.java}})'
     if: always()
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     strategy:
       fail-fast: false
       matrix:
diff --git a/99-integration/dubbo-samples-nacos-legacy/case-configuration.yml b/99-integration/dubbo-samples-nacos-legacy/case-configuration.yml
index 6ce1735..3383ab9 100644
--- a/99-integration/dubbo-samples-nacos-legacy/case-configuration.yml
+++ b/99-integration/dubbo-samples-nacos-legacy/case-configuration.yml
@@ -17,7 +17,7 @@
 services:
   nacos:
     # set large DB_POOL_CONNECTION_TIMEOUT (provided since nacos-server v2.3.1+) to avoid login timeout.
-    image: nacos/nacos-server:v2.3.1-slim
+    image: nacos/nacos-server:v2.5.1-slim
     environment:
       - PREFER_HOST_MODE=hostname
       - MODE=standalone